The present invention is concerned with motor-generator systems, and is more especially directed to a gas turbine electric starter.
U.S. patent application Ser. No. 11/974,399, filed Oct. 12, 2007 discloses a rim driven induction motor/generator, for operation with a turbine apparatus, comprising: at least one outer ring stator and at least one inner ring rotor concentric with said ring stator; wherein said turbine apparatus comprises: a turbine having a part fixed to at least one of said rotor or rotors; a central shaft concentric with at least one of said stator or stators; bearing means between said central shaft and said turbine; wherein the tips of said turbine are fixed to an inside surface of said inner ring.
The paper: “Scale Model Testing of a Commercial Rim-Driven Propulsor Pod”, by Lea et al, published by SNAME in the “Journal of Ship Production”, Volume 19, Number 2, 1 May 2003, pp. 121-130(10), incorporates the following Abstract: Podded propulsion is gaining more widespread use in the marine industry and is prevalent in newer cruise ships in particular. This propulsion system can provide many advantages to the ship owner that include increased propulsion efficiency, arrangement flexibility, payload, and harbor maneuverability. A new, unique podded propulsor concept is being developed that allows optimization of each element of the system. The concept comprises a ducted, multiple-blade row propulsor with a permanent magnet, radial field motor rotor mounted on the tips of the propulsor rotor blades, and the motor stator mounted within the duct of the propulsor. This concept, designated a commercial rim-driven propulsor pod (CRDP), when compared to a conventional hub-driven pod (HDP), offers improved performance in a number of areas, including equal or improved efficiency, cavitation, and hull unsteady pressures. The combination of these CRDP performance parameters allows the ship designer much greater flexibility to provide improved ship performance as compared to that of an HDP. A CRDP is being developed to power a panama-size cruise vessel. The paper addresses the hydrodynamic performance of that CRDP design demonstrated at 1/25th scale as tested at the Hamburg Ship Model Basin, Hamburg Germany (HSVA).
Van Blarcom et al. (2004) describe the design of a rim-driven propulsor. The concept is comprised of a ducted multiple blade row propulsor with a permanent magnet radial flux motor rotor mounted at the tips of the propulsor blades and the motor stator mounted within the duct. The rotor shaft and bearings are housed in a relatively small hub, which is free flooding and supported by a set of downstream stator blades.
U.S. Pat. No. 6,837,757 to Van Dine et al, is directed to a rim-driven propulsion pod arrangement. In the embodiments described in the specification, a rim-driven propulsion pod arrangement has a cylindrical housing with a duct providing a flow path for water and a rotor assembly supported from a central shaft and containing a rotating blade row and driven by a rim drive permanent magnet motor recessed in the housing. An array of vanes downstream from the rotating blade row is arranged to straighten the flow of water emerging from the rotating blade row. Radial bearing members on the rotor have a hardness less than that of the shaft on which the rotor is supported and relatively soft protrusions are provided in the space between the rotor and the housing to limit excursion of the rotor. A thrust bearing has wedges arranged to form a water wedge between facing surfaces of the rotor and the rotor support during rotation of the rotor.
U.S. Pat. No. 6,152,791 to Sinko et al is directed to an external electric drive propulsion module arrangement for swath vessels. In the embodiments described in the specification, a SWATH vessel has a superstructure supported by strut members from a pair of pontoons and each pontoon has a propulsion module removably attached to the rear end of the pontoon. The propulsion module has a self contained propulsion system including a module body with a longitudinal water passage, a rim drive electric motor, a row of rotatable blades, and an inlet opening at the forward end of he cowl member which is arranged to draw in the boundary layer of water flowing along the pontoon to which the propulsion module is attached. Spaced vanes are provided at the inlet opening to block objects from being drawn into the longitudinal passage.
U.S. Pat. No. 5,967,749 to Eaves et al. is directed to a controllable pitch propeller arrangement. In the particular embodiments described in the specification, a controllable pitch propeller arrangement includes a plurality of propeller blades supported from a central hub which is rotatably mounted on a shaft in which each blade is pivotally supported from the central hub. Two radial pins extending from the outer ends of each of the blades are received in corresponding rims having peripherally disposed permanent magnet arrays. The rims are rotated to drive the propeller by energizing the coils in a stator assembly surrounding the rims and the pitch of the blades is changed by changing the phase relationship of the current supplied to the stator coils to change the angular relation of the rims.
U.S. Pat. No. 6,956,310 to Knox is directed to a submersible pump motor having rotor sections spaced apart from each other with bearings located between. The bearings support the shaft of the rotor within a stator. The bearing is stationary and has a cavity in its outer periphery. A metallic coiled member is positioned along the circumference of the bearing, and rests in the cavity on the outside diameter of the bearing. The coiled member engages the bearing and the inner wall of the stator to prevent rotation of the bearing.